The present invention relates to an optical disc recording apparatus for recording information on an optical disc, such as a CD-R (Compact Disc-Recordable) and a CD-RW (Compact Disc-ReWritable), and to a control method therefor.
An optical disc recording apparatus adapted to record information on an optical disc by irradiating the optical disc with light beams to thereby change the optical property of a recording layer thereof has been widely utilized.
FIG. 17 is a view schematically illustrating an optical disc 5 typified by a CD-R.
As illustrated in FIG. 17, guide grooves (or pre-grooves) P are preliminarily formed in an optical disc 5. When data is recorded thereon and reproduced therefrom, an operation of controlling a tracking servo and a spindle motor is performed by utilizing the pre-grooves P. Each of the pre-grooves slightly meanders (or wobbles) in a radial direction of the optical disc 5. ATIP (Absolute Time In Pre-Groove) information including absolute time information on the optical disc 5 is detected by detecting displacement of return light of a light beam irradiated on the pre-grooves.
FIG. 18 is a view illustrating the configuration of an optical disc recording apparatus for recording data on the optical disc 5.
An optical head 110 is operative to output laser light according to recorded data, which is EFM (Eight to Fourteen Modulation)-modulated and supplied from a data encoder 160, and to write the recorded data, under the control of a control portion (not shown).
An analog front end portion 120 detects an wobble signal (that is, a signal corresponding to a wobble on the optical disc 5) having a frequency of 22.05 kHz (in the case that the linear velocity is set at a single speed (in the following cases, the linear velocity is set in the same way)), and then outputs the wobble signal to an ATIP decoder 130.
The ATIP decoder 130 demodulates obtains wobble signals supplied from the analog front end portion 120 to thereby obtain ATIP information and time information on the optical disc. Moreover, the ATIP decoder 130 extracts an ATIP clock signal having a frequency of 6.3 kHz.
A PLL circuit 140 employs an ATIP clock signal, which is supplied from the ATIP decoder 130, as a reference signal, and outputs a clock signal, which has a frequency that is a multiple of the frequency of the reference signal, to a frequency divider 150.
The frequency divider 150 frequency-divides a clock signal, which is outputted from the PLL circuit 140, with a predetermined frequency division ratio, and then outputs a resultant signal to a data encoder 160 as a recording clock signal having a frequency of 4.3218 MHz (incidentally, the linear velocity is equivalent to a single speed).
The data encoder 160 adds data, which is represented by an error detection signal, to recording data outputted sent from a host computer, and then encodes resultant data and performs an EFM thereon. Subsequently, the data encoder 160 outputs the recorded data, on which an EFM has been performed, to the optical head 110 in response to a recording clock signal outputted from the frequency divider 150.
Thus, the optical disc recording apparatus 100 writes recording data according to a recording clock signal obtained by using an ATIP clock signal as a reference signal. However, in the case that the rotation of the optical disc 5 is disturbed owing to vibrations and blemishes on the disc 5, and that a malfunction of a servo circuit (not shown) for controlling the rotation of the optical disc 5 occurs, the positional deviation between the ATIP information and the recorded data occurs.
Such a positional deviation is accumulated without being corrected until the writing of the recording data is completed. Thus, in the case that such a positional deviation frequently occurs, the optical disc recording apparatus has encountered the problem that the positional deviation exceeds a tolerance defined by standard specifications (for example, Orange Book standards) for CDs.